January 26, 2011
Analyzing the extent of marginal grasslands, including abandoned and degraded grassland, using data on soil, topography, climate and current land use, Ximing Cai of the University of Illinois at Urbana−Champaign and colleagues calculate that using low-impact high-diversity (LIHD) perennial grasses as biofuel feedstocks could meet up to 56 percent of current liquid fuel consumption. They estimate up to 1.4 billion hectares of land in Africa, China, Europe, India, South America, and the continental United States could be available for such "second-generation" energy crops. The researchers included only areas that would be watered by rainfall, not irrigation, in order to minimize the potential impact on food production.
But the researchers caution that the rosy projections could change once the effects of climate change are factored in. Furthermore, population growth and increasing affluence are expected to significantly boost energy demand in the future, increasing the need for land. Finally the researchers did not account for the impacts invasive species could have in non-native landscapes or social issues such as land tenure.
Still the authors say the study is a good starting point for future research that could affect policy decisions.
"We hope this will provide a physical basis for future research," said Dingbao Wang, a co-author who is now at the University of Central Florida. "For example, agricultural economists could use the dataset to do some research with the impact of institutions, community acceptance and so on, or some impact on the market. We want to provide a start so others can use our research data."
Ximing Cai, Xiao Zhang, Dingbao Wang. Land Availability for Biofuel Production. Environmental Science & Technology. 2011, 45 (1), pp 334–339. doi: 10.1021/es103338e